We plan to continue our studies on the metabolism of gastrin, the sources of gastrin, the mechanism of action, release and transport of gastrin, the processes by which gastrin is catabolized and the relationships between gastrin and other hormone of gastrointestinal, pancreatic and pituitary origin in man and animals during different physiological states. We plan to study the effects of antrectomy and vagotomy on gastrin response to alcohol and food in dogs. We plan to study the effects of acetylcholine on gastrin in normal dogs, dogs with gastric fistulas and gastrectomized dogs. We plan to study the effects of insulin and selective proximal vagotomy on basal gastrin, food-stimulated gastrin and gastric acid secretion in Heidenhain pouch dogs. We plan to study the effects of food on tissue and serum levels of gastrin in rats. We plan to study the effects of graded vagotomy and vagal stimulation on tissue and serum gastrin in dogs. We intend to study the effects of calcium on gastrin and gastric secretion in intact and thyroidectomized dogs and pigs. We plan to determine the effects of anesthesia on release and catabolism of gastrin and on gastic secretion. We will study the effects of steroids on serum gastrin concentration in dogs. We will study, in dogs, the effects of injections of antigastrin antibodies on gastrin release and gastric acid secretion. We intend to develop and validate radioimmunoassays for measuring the concentrations of secretin, glucagon, insulin, calcitonin and growth hormone in tissues and body fluids of man and experimental animals.